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Selective photosynthesis of imines from biomass-derived aldehydes over Ni/TiO_(2)

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Rare Metals 2024年第3期43卷 1116-1124页

作者： Wu-Lin Li qing-qing zhang Lin Dong Wen-Jun zhang Li-Li Lin Zu-Peng Chen Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing210037China Institute of Industrial Catalysis State Key Laboratory of Green Chemistry Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

Photocatalytic reductive amination of biomass-derived aldehydes is a desirable way to selectively upgrade biomass into value-added nitrogen-containing chemicals under mild ***,it is challenging to produce imines in high selectivity because of the undesirable side reactions caused by the activity of functional ***,we demonstrate the highly reactive and selective production of imines from biomass derived aldehydes via the photocatalytic reductive amination,using a defective TiO_(2)supported nickel *** employment of methanol as the hydrogen donor and ammonia solution as the nitrogen source avoids the use of high-pressure H_(2)and expensive amines,rendering the current catalytic process safe,economical,and environmentally *** depth investigations attribute the improved separation and transfer of photogenerated charge carriers to the presence of oxygen vacancies and decorated Ni nanoparticles,thereby accelerating the production of imines from benzaldehyde amination(conversion,95.8%;seleetivity,95.2%).Furthermore,the developed system could be easily translated to the photocatalytic conversions of various biomass derived aldehydes,which provided an example of a cost-effective and sustainable approach for the valorization of biomass derived feedstocks.

关键词： Photocatalysis Biomass derivatives Imines Reduction amination Heterogeneous catalyst

A novel weld-pool-length monitoring method based on pixel analysis in plasma arc additive manufacturing

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Advances in Manufacturing 2024年第2期12卷 335-348页

作者： Bao-Ri zhang Yong-hua Shi Bionic Robot Research Department Ji Hua LaboratoryFoshan528200GuangdongPeople’s Republic of China Guangdong Provincial Engineering Research Center for Special Welding Technology and Equipment School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640People’s Republic of China

The real-time monitoring of the weld pool during deposition is important for automatic control in plasma arc additive *** obtain a high deposition accuracy,it is essential to maintain a stable weld pool *** this study,a novel passive visual method is proposed to measure the weld pool *** the proposed method,the image quality was improved by designing a special visual system that employed an endoscope and a *** also includes pixel brightness-based and gradient-based algorithms that can adaptively detect feature points at the boundary when the weld pool geometry *** algorithm can also be applied to materials with different solidification *** was performed to measure the real weld pool length in world coordinates,and outlier rejection was performed to increase the accuracy of the ***,tests were carried out on the intersection component,and the results showed that the proposed method performed well in tracking the changing weld pool length and was applicable to the real-time monitoring of different types of materials.

关键词： Plasma arc additive manufacturing(PAAM) Weld pool geometry Gradient analysis Real-time detection

Baeyer-Villiger oxidation of ketones with hydrogen peroxide catalyzed by Sn-aniline complex

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Chinese Chemical Letters 2007年第1期18卷 4-6页

作者： qing hua zhang Shou Feng Wang Zi Qiang Lei Key Laboratory of Polymer Materials of Gansu Province College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 China

Sn-aniline complex was prepared by a simple procedure. Cyclic and acyclic ketones were oxidized into lactones or esters with very high selectivity and yield with 30% hydrogen peroxide in the presence of Sn-aniline com... 详细信息

关键词： Baeyer-Villiger oxidation Sn-aniline complex Ketone oxidation Hydrogen peroxide

Preparation of Low-dielectric Permittivity Polyimide Resins with High Surface Activity from Chemically Bonded Hyperbranched Polysiloxane

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Chinese Journal of Polymer Science 2021年第9期39卷 1200-1210页

作者： Xiu-Ting Li Xiao-Meng Zhu Jie Dong Xin Zhao qing-hua zhang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China

Thermosetting resin matrix is the key component of advaneed wave-tra nsparent composites,where low dielectric constant,excellent processability,high thermal stability,as well as good bonding ability are required for ***,we prepared a series of phenylethynyl terminated polyimide(PI)resins by grafting amine-functi onalized hyperbra nched polysiloxane(HBPSi)to PI chains during the in situ *** effects of HBPSi on the processability of oligomers,molecular packing,thermal stability,dielectric property and bonding ability to reinforce Kevlar fibers of the cured PI/HBPSi composite resins have been examined in *** dielectric constants of the cured composite resins were greatly reduced from 3.29 to 2.19 without compromising its processability and thermal ***,the 10 wt%HBPSi-containing PI resin demonstrated better bonding ability to reinforce fibers with the in terfacial shear strength(IFSS)of 37.64 MPa,compared with that of neat PI-6 matrix(27.34 MPa),and better adhesion to metal with the lap shear strength of 10.48 MPa,50%higher than that of neat resin PI-6(6.98 MPa).These resultant PI/HBPSi composite resins exhibit excellent comprehensive properties,indicating their great potential as low-dielectric constant resin matrix in radar radome.

关键词： Hyperbranched polysiloxane Polyimide resin Low dielectric constant Processability Bonding ability

Influence of pressure disturbance wave on dynamic response characteristics of liquid film seal for multiphase pump

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Petroleum Science 2024年第3期21卷 2048-2065页

作者： qing-Ping Li Jin-Ya zhang Jia-Xiang zhang Yong-Xue zhang CNOOC Research Institute Company Limited Beijing100028China State Key Laboratory of Natural Gas Hydrate Beijing100028China College of Mechanical and Transportation Engineering China University of PetroleumBeijing2249China

Slug flow or high GVF(Gas Volume Fraction)conditions can cause pressure disturbance waves and alternating loads at the boundary of mechanical seals for multiphase pumps,endangering the safety of multiphase pump *** mechanical seal model is simplified by using periodic boundary conditions and numerical calculations are carried out based on the Zwart-Gerber-Belamri cavitation ***(User Define Function)programs such as structural dynamics equations,alternating load equations,and pressure disturbance equations are embedded in numerical calculations,and the dynamic response characteristics of mechanical seal are studied using layered dynamic mesh *** results show that when the pressure disturbance occurs at the inlet,as the amplitude and period of the disturbance increase,the film thickness gradually *** the fundamental reason for the hysteresis of the film thickness change is that the pressure in the high-pressure area cannot be restored in a timely *** maximum value of leakage and the minimum value of axial velocity are independent of the disturbance period and determined by the disturbance *** mutual interference between enhanced waves does not have a significant impact on the film thickness,while the front wave in the attenuated wave has a promoting effect on the subsequent film thickness changes,and the fluctuation of the liquid film cavitation rate and axial velocity under the attenuated wave condition deviates from the initial *** with pressure disturbance conditions,alternating load conditions have a more significant impact on film thickness and *** actual operation,it is necessary to avoid alternating load conditions in multiphase pump mechanical seals.

关键词： Multiphase pump Liquid film seal Pressure disturbance wave Dynamic response characteristics

Association between glucose-lowering drugs and circulating insulin antibodies induced by insulin therapy in patients with type 2 diabetes

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World Journal of Diabetes 2024年第7期15卷 1489-1498页

作者： Peng zhang qing Jiang Bo Ding Reng-Na Yan Yun Hu Jian-hua Ma Department of Endocrinology Nanjing First HospitalNanjing Medical UniversityNanjing 210000Jiangsu ProvinceChina Department of Endocrinology The Affiliated Wuxi People's Hospital of Nanjing Medical UniversityWuxi Medical CenterWuxi 214000Jiangsu ProvinceChina

BACKGROUND Insulin antibodies(IAs)affect blood glucose control in patients receiving insulin *** To investigate the relationship between different hypoglycemic treatments and IAs in patients with type 2 diabetes mellitus(T2DM).METHODS This cross-sectional,retrospective study included 1863 patients with T2DM who were receiving exogenous insulin *** patients received stable antidiabetic therapy in the last 3 months and IA levels were measured using an iodine-125 *** A total of 1863 patients were *** were 902(48.4%)patients who had positive IAs(IA level>5%),with a mean IA level of 11.06%(10.39%-11.72%).IA levels were positively correlated with high fasting blood glucose(odds ratio=1.069,P<0.001).The proportion of positive IAs was lowest in patients using glargine only(31.9%)and highest in patients using human insulin only(70.3%),P<*** IA levels in patients using sulfonylureas/glinides(8.3%),metformin(9.6%),and dipeptidyl peptidase-4 inhibitors(8.2%)were all lower than in patients without these drugs(all P<0.05).CONCLUSION Nearly half of patients on insulin therapy have positive IA antibodies,and IA antibody levels are associated with blood glucose *** glargine and a combination of oral glucose-lowering drugs were correlated with lower IA levels.

关键词： Insulin antibodies Insulin therapy Glucose-lowering drugs Glargine Type 2 diabetes

Necroptosis contributes to non-alcoholic fatty liver disease pathoetiology with promising diagnostic and therapeutic functions

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World Journal of Gastroenterology 2024年第14期30卷 1968-1981页

作者： Hong-Ju Sun Bo Jiao Yan Wang Yue-hua zhang Ge Chen Zi-Xuan Wang Hong Zhao qing Xie Xiao-hua Song Department of General Medicine Qingdao Central HospitalUniversity of Health and Rehabilitation Sciences(Qingdao Central Medical Group)Qingdao 266042Shandong ProvinceChina Department of Gastroenterology Qingdao Central HospitalUniversity of Health and Rehabilitation Sciences(Qingdao Central Medical Group)Qingdao 266042Shandong ProvinceChina Department of Medical Administration Qingdao Central HospitalUniversity of Health and Rehabilitation Sciences(Qingdao Central Medical Group)Qingdao 266042Shandong ProvinceChina qingdao Medical College Qingdao UniversityQingdao 266042Shandong ProvinceChina Department of Infectious Diseases Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China

Nonalcoholic fatty liver disease(NAFLD)is the most prevalent type of chronic liver ***,the disease is underappreciated as a remarkable chronic disorder as there are rare managing *** studies have focused on determining NAFLD-caused hepatocyte death to elucidate the disease pathoe-tiology and suggest functional therapeutic and diagnostic ***,ferroptosis,and necroptosis are the main subtypes of non-apoptotic regulated cell deaths(RCDs),each of which represents particular *** the complexity of the findings,the present study aimed to review these types of RCDs and their contribution to NAFLD progression,and subsequently discuss in detail the role of necroptosis in the pathoetiology,diagnosis,and treatment of the *** study revealed that necroptosis is involved in the occurrence of NAFLD and its progression towards steatohepatitis and cancer,hence it has potential in diagnostic and therapeutic ***,further studies are necessary.

关键词： Nonalcoholic fatty liver disease Apoptosis Necroptosis Cell death Diagnosis Treatment

Competitive assembling strategy to construct carbon nitride homojunctions for boosting photocatalytic performance

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Journal of Materials Science & Technology 2024年第5期172卷 23-32页

作者： hua-Wei zhang Yuan-Yuan Li Bo Li Jing-Hui Shi Tao huang Gui-Fang huang Anlian Pan Wangyu Hu Wei-qing huang School of Physics&Electronic Engineering Zhengzhou University of Light IndustryZhengzhou 450002China Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education&Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices School of Physics and ElectronicsHunan UniversityChangsha 410082China College of Materials Science and Engineering Hunan UniversityChangsha 410082China

Both morphology and composition have a great influence on the properties and functions of materials,however,how to rational modulate both of them to achieve their synergistic effects has been a longstanding ***,we demonstrate a competitive assembling strategy for the construction of metal-free graphite carbon nitride(CN)homojunctions in which morphology and composition can be easily controlled simultaneously by only changing the ratio of assembly raw *** homojunctions are comprised of porous nanotubular S-doped CN(SCN)grafted with CN nanovesicles,which are derived from thermal polycondensation of melamine-thiocyanuric acid(M-T)/melamine-cyanuric acid(M-C)supramolecular hybrid *** unique architecture and component engineering endows the novel SCN-CN homojunction with abundant active sites,enhanced visible trapping ability,and intimate interface *** a result,the synthesized SCN-CN homojunctions demonstrate high photocatalytic activity for hydrogen evolution and pollutant *** developed strategy opens up intriguing opportu-nities for the rational construction of intricate metal-free heterostructures with controllable architecture and interfacial contact for applications in energy-related fields.

关键词： Competitive assembling strategy Supramolecular hybrid blocks Homojunctions Graphite carbon nitride Photocatalytic

Lightweight Malicious Code Classification Method Based on Improved Squeeze Net

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Computers, Materials & Continua 2024年第1期78卷 551-567页

作者： Li Li Youran Kong qing zhang School of Computer and Control Engineering Northeast Forestry UniversityHarbin150040China

With the growth of the Internet,more and more business is being done online,for example,online offices,online education and so *** this makes people’s lives more convenient,it also increases the risk of the network being attacked by malicious ***,it is important to identify malicious codes on computer systems ***,most of the existing malicious code detection methods have two problems:(1)The ability of the model to extract features is weak,resulting in poor model performance.(2)The large scale of model data leads to difficulties deploying on devices with limited ***,this paper proposes a lightweight malicious code identification model Lightweight Malicious Code Classification Method Based on Improved SqueezeNet(LCMISNet).In this paper,the MFire lightweight feature extraction module is constructed by proposing a feature slicing module and a multi-size depthwise separable convolution *** feature slicing module reduces the number of parameters by grouping *** multi-size depthwise separable convolution module reduces the number of parameters and enhances the feature extraction capability by replacing the standard convolution with depthwise separable convolution with different convolution kernel *** addition,this paper also proposes a feature splicing module to connect the MFire lightweight feature extraction module based on the feature reuse and constructs the lightweight model *** malicious code recognition accuracy of LCMISNet on the BIG 2015 dataset and the Malimg dataset reaches 98.90% and 99.58%,*** proves that LCMISNet has a powerful malicious code recognition *** addition,compared with other network models,LCMISNet has better performance,and a lower number of parameters and computations.

关键词： Lightweight neural network malicious code classification feature slicing feature splicing multi-size depthwise separable convolution